Summing interface?

[MidniteMachinist]

I just picked up a universal-head mill. The head rotates 90*, and I'd like to put a rotary encoder on it. I know I can use the W-axis input for this.

However, the head is on a ram that moves in and out along the Y-axis, and I'd also like to put an additional quadrature scale on that, and sum it with the Y-axis table travel scale. This would also require the use of the W-axis input.

So... 5 encoders, 4 inputs. Would I be able to use something like THIS to combine the Y-axis scales before the TouchDRO board, thus keeping the W-axis input free for the rotary encoder?

[Yuriy]

I just picked up a universal-head mill. The head rotates 90*, and I'd like to put a rotary encoder on it. I know I can use the W-axis input for this.

However, the head is on a ram that moves in and out along the Y-axis, and I'd also like to put an additional quadrature scale on that, and sum it with the Y-axis table travel scale. This would also require the use of the W-axis input.

So... 5 encoders, 4 inputs. Would I be able to use something like THIS to combine the Y-axis scales before the TouchDRO board, thus keeping the W-axis input free for the rotary encoder?

This would work (at least I don't see why not).

[MidniteMachinist]

Thanks, Yuriy! I figured... It's still outputting a quadrature signal.

I suppose the crux of it, is whether the scales have exactly the same CPI. I imagine if they don't (or, at least, if the CPI is too dissimilar), it'll result in inaccuracy.

If I do end up getting that interface, I'll report back.